Caesar Cipher

Description

The Caesar cipher is one of the earliest known encryption techniques. It works by shifting each letter in the alphabet by a fixed number of positions. For example, with a shift of 3, 'A' becomes 'D', 'B' becomes 'E', and so on.

Your task: Decode the following encrypted message: zhoogrqhwhdp

 Links

• https://en.wikipedia.org/wiki/Caesar_cipher

QR CyberChef Challenge

Description

Follow these steps to uncover the hidden flag using CyberChef:

1. Open CyberChef (link below)

2. Drag the provided QR code into the input field (download it in your laptop first).

3. Add 'Parse QR Code' to extract data. This step helps us read a QR code and extract the information from it.

4. Add 'From Base64' from the operations. This step turns special text (Base64) into another format.

5. Add 'From Binary' from the operations. This step changes a code made of 1s and 0s (Binary) into regular words.

6. Add 'XOR' with key: supersecret. Here, we will mix our information using a supersecret word to keep it safe.

7. Add 'From Hex' to convert the output. This step converts special numbers (Hex) into regular words.

8. Add 'Caesar Box Cipher' with Box Height: 3. We’ll arrange our text into boxes that are 3 rows high to create a secret message.

9. Find the flag in the output. Follow the steps carefully to reveal the secret flag.

 Links

• https://gchq.github.io/CyberChef/
• https://cyber.kent.ac.uk/events/CyberFirst/Girls_Development_Day_20241008/qrcode.png

The Secret Number

Description

You are given the outcome of a sequence of operations performed on a secret number x.

Work backwards to find the original number. Operations:

1. Start with number x

2. Multiply by 2

3. Add 10

4. Divide the result by 4

5. Subtract 3

6. Final result is 5 Find the original value of x

 Links

• https://www.mathsisfun.com/definitions/inverse-operation.html

Hidden Message – Encoding

Description

You intercepted an encoded sentence. Use your knowledge of simple character shifts (Caesar cipher) to decode it. Encoded message: Uifsf jt b tfdsfu nfttbhf Once decoded, the sentence reveals the hidden flag.

Links

• https://www.dcode.fr/caesar-cipher

Cookie Clue

Description

Websites use 'cookies' to remember information about you, like your username or preferences. They're like little notes saved in your browser! Your task: This page has set a cookie with a secret message. Can you find it? STEPS:

1. Open your browser's Developer Tools (Press F12, or right-click → Inspect)

2. Look for the 'Application' tab (Chrome) or 'Storage' tab (Firefox)

3. In the left sidebar, expand 'Cookies' and click on this website

4. Find the cookie named 'secret_challenge'

5. The value of that cookie is your flag! SUBMIT IT AS: FLAG{cookie_value_you_found} NOTE: You need to actually inspect the cookies on this challenge page to find the answer!

Links

• https://developer.chrome.com/docs/devtools/application/cookies/
• https://www.kaspersky.com/resource-center/definitions/cookies

Console Secret

Description

Developers leave clues in the browser console all the time! Your mission is to open the console on this page and read the secret message. STEPS:

1. Press F12 (or Cmd+Option+I on Mac) to open Developer Tools

2. Click on the "Console" tab

3. Look for the message that appears when this challenge loads

4. The message includes the exact flag you need to submit NOTE: The secret only shows up in the console – it will NOT appear on the page itself!

Links

• https://developer.chrome.com/docs/devtools/console/
• https://firefox-source-docs.mozilla.org/devtools-user/web_console/index.html

Element Inspector

Description

Web browsers let you peek behind the scenes of any webpage! This challenge places a special badge on the page. Inspect it to reveal the hidden code. STEPS:

1. Look near the top of this page for the image of alex the kid

2. Right-click the badge and choose "Inspect" (or use Ctrl+Shift+I / Cmd+Option+I)

3. In the Elements panel, find the badge element

4. Check its alt id attribute – that's your answer! NOTE: The badge shows up visually, but the flag only lives inside its HTML attributes.

Links

• https://developer.chrome.com/docs/devtools/dom/
• https://www.w3schools.com/tags/att_global_data.asp

Robot Rules

Description

Websites have a special file called 'robots.txt' that tells search engine robots which pages they can visit! Sometimes interesting directories are listed there. Your task: Check the robots.txt file of THIS website to find a secret path! STEPS:

1. Look at the URL of this page in your browser

2. Remove everything after the domain name

3. Add /robots.txt to the end

4. For example: if you're on 'example.com/challenge/123', go to 'example.com/robots.txt'

5. Find the comment that says 'Secret path:' and look at what follows it

6. Submit it as FLAG{path_you_found} NOTE: Real websites use robots.txt to tell search engines what to index. Hackers often check this file first to discover hidden directories!

Links

• https://www.robotstxt.org/
• https://en.wikipedia.org/wiki/Robots.txt